Vacuum pump



July 12, 1927. f 1,635,271

` C. H. HAPGOOD VACUUMPUMP Filed Aug. l2 1925 2 Sheets-Sheet l 1,635,271 July 12 1927- C, H. HAPGOQD VACUUM PUMP Filed Aug. l2, 1925 2 Sheets-Sheet P. JA. 7 V/cz Patented July 12, 1927.

UNITED STATES PATENT orrice.

CYRUS HOWARD HAPGOOD, 0F NUTLEY, NEW JERSEY, ASSIGNOR TO THE DE LAVAL SEPARATOR CDMPANY, 0F NEW YORK, N. Y., A CORPORATION 01E' NEW JERSEY.

'VACUUM PUIP.

Application led August 12, 1925. Serial` No. 49,688.

Vacuum pumps ot the type shown in the patents to Leitch, No. 1,367.554, February 8, 1921. and Hall, No. 1,374,650, April 12, 1921, and in an application filed by me May 3, 1924, as Serial No. 710,730, are in successful commercial use, especial-ly to create a partial vacuum' in milking machines, including the pipe lines between the pumps and the milking machine units. While a sanitary trap has been positioned on the pipe line, considerable diiiiculty has been experienced with pipe scale between the trap and the pump working its way through the pipe to the inlet of the pump and thence through the ports in the housing or housing cap into the bore of the pump casing. In some instances, the scale jams in the pump so that it cannot be revolved. ln other cases, the scale travels around the inside of the pump casing and scores the wearing surfaces.

The object of the invention is to so modify the pump structure, especially the -air pas" sage between the air, inlet and the chamber or chambers which directly communicate with the space between the bore ot the pump casingand the rotor,that any scale which is sucked into the pump will be deposited in a catch-pocket or trap specially provided `for that purpose and cannot pass, with the air, into the space between the rotor and the bore of the housing or into any part of the pump where it might interfere with the free rotation of the rotor.

A preferred embodiment of the invention is shown in the accompanying drawings, in which- Fig. 1 is a vertical sectional view of a vacuum pump embodying my invention, the. rotor being omitted.

Figt 2 is a plan view of a part of the pump, partly 'broken away.

Fig. 3 is a vertical section on the line 3-3 of Fig. 1.

Fig. 4 is a section on the line 4 4 of Fig. 1.

n the outside of the pump housing a isy lVithin the casing a is a web d which extends from the upper part of the casing downward toward. but terminatingr substantially short of, the bottom of the chamber within the casing. Thereby there are'formed an air passage c outside the web and directly communicating with the inlet c, a pocket or trap f below the web, and an air passage g under the web.

At opposite sides of the passage g are formed portsV h which may communicate with chambers i formed in opposite end heads of the pump casing, which chambers communicate directly, through long arcuate openings j, with the space between the rotor and the bore of the casing.

Air passing` into the inlet c is compelled to take a tortuous course to enter the pump proper. As indicated by the arrows, it is compelled to travel down the passage c, thence around the edge of web d over the pocket f, thence up into passage g, thence laterally through passages h into the pump head chamber passages z' and thence laterally through openings into the space between the rotor and the pump casing. As the air travels at considerable velocity and is compelled to abruptly change or reverse its direction, in passing from passage e to passage g, pipe scale and any other solid material, such as particles of dirt, are deposited in the bottom of pocket f, and remain there, only clean air passing into the bore of the pump.

The wall of the casing b is bored and tapped to form a clean-out opening a: communicating with the bottom of the pocket f. This opening will be closed by a plug y, which will remain in place during the operation of the pump and which may be removed periodically to clean out the accumulated deposits. y

Having now fully described my invention, what I claim and desire to protect by Letters Patent is:

1. In a vacuum pump, the combination with a pump housing and a casing interior thereto and aced therefrom and providing an arcuate air space between them, the carsing having an air inlet at one end of said space, the other end of said space being closed, of a web extending between the housing and casing from the end of said space adjacent the air inlet toward but terminating short of the closed end of said space, there being lateral outlets communicating with lll the interior of the pump housing, from' that part of said space between said web and the housing, thereby providing a confined and tortuous passage for air through said space back and forth in opposite direction and laterally from between the web and the pump housing.

2. In a vacuum pump, the combination with a pump housing and a casing exterior thereto extending around a part of the circumference of the housing, of a web extending circumferentially downward from the upper end of the casing toward, and vterminating short of, the lower end of the casing, and forming communicating outer :rnd inner air passa es, an air inlet port comunicating with t e upper part of the outer passage, air outlet ports at opposite sides of the inner passage, chambers carried by the housing and with which the air outlet ports communicate, and laterally extending air inlet ports between said chambers and the housing interior.

web extending downward from the upper.

end of the casing toward, and terminating short of, the lower end of the casing, and

forming an air passage comprising two arcuate sections and an intermediate pocket, ports, respectively for admission and discharge of air, communicating respectively with the passage section outside the web and the passage section inside the web, the lower part of the housing having a lateral opening communicating with said pocket,

a'nd a removable plug closing the opening.

In testimony of which invention, I have hereunto set my hand, at New York, on this 7th day of August, 1925.

cYRUs HOWARD HAPGooD. 

